1. Field
The field of the invention is devices for leveling the bodies of vehicle drawn trailers when parked.
2. State of the Art
A recurrent problem in the use of vehicle drawn trailers is parking upon uneven ground, wherein the trailer tends to repose into a tilted position if allowed to rest upon its wheels. Often, standard axle jacks do not easily lift the trailer sufficiently to level the trailer. Even then, chocks or the like must be placed to support both wheel ends of the axles for parking. Several auxiliary devices have been proposed wherein a jack engageable member is secured to the trailer frame to extend laterally for purchase of jacks beside, rather than beneath, the trailer body. In U.S. Pat. No. 3,802,664, a crossbar is secured to side members of the trailer frame to extend beyond the outside trailer walls to provide a vertical jacking plate. The latter is engaged by a conventional automobile bumper jack. One serious shortcoming is that crossbar can only be secured below the frame members so that it projects downwardly, which is particularly vulnerable to dragging against the ground of rough roads and driveways. With this device, the bumper jack""s grasp upon the plates is tenuous at best, with no positive lock between jack and plate.
Clearly, a need remains for a trailer attached apparatus for jacking the trailer to a laterally and longitudinally level position when parked on sloping and uneven ground.
With the foregoing in mind, the shortcomings in the prior art trailer jacking devices are eliminated or substantially alleviated by the present invention, which provides at least one jack attachment assembly secured to a lowermost longitudinal member of a trailer body frame, preferably without extending below the plane of the bottom of such members. This avoids creating any additional obstruction to the use of the trailer on uneven roads and terrains. A jack attachment member extends horizontally beyond the associated trailer sidewall to there fit about a lifting member of a trailer jacking device or jack. Preferably, this jack lifting member extends horizontally inwardly, firmly secured such as by welding to the moving outer shell or housing of the jack, and telescopically joins the outwardly extending jack attachment member. This virtually eliminates the possibility of the trailer becoming disengaged from the jack during use.
Preferably, a forward and a rearward pair of jack attachment assemblies are used, each comprising a pair of horizontal tubular members each with an affixed vertical attachment flange at an innermost end connecting with and bolted to a respective trailer body frame longitudinal member. To relieve any localized twisting force upon the trailer body frame members from the jacking force, preferably an end flanged cross-brace joins the jack attachment members of each pair, the end flanges each being bolted to the respective attachment flanges through a respective trailer body frame longitudinal member. Each cross-brace may comprise a monolithic beam-like member, or slideably associated segments rigidly secured together to span between the trailer body frame longitudinal members.
The jack attachment assemblies and cross-brace, therefore, t; provide a substantially stronger and more rigid support of the trailer body in jacked up position than is provided by any of the prior art methods and apparatus for this purpose.